If you happened to be inNew York City’sUnion Squareon September 27, you may have seen something unusual — “Joe the Pig”, decked out in a Hawaiian shirt, and a crowd of concerned consumers calling on Trader Joe’s to help get Joe off drugs.

The crowd, gathered in front of Trader Joe’s flagship NYC store, was there to deliver a simple message: using antibiotics on livestock that don’t need them threatens the health of people who do. And Trader Joe’s can actually do something about it.

Trader Joe’s is already a leader in environmentally conscious food sourcing. Today, the company’s customers asked it to use its buying power to help change the way our livestock industry raises the chicken, pigs, cows, and other food animals that end up on our plates. With a petition signed by more than 557,772 worried consumers in hand, those gathered asked Trader Joe’s to source and sell only meat raised without antibiotics. With growing momentum across the nation to get antibiotics out of our meat, the event spotlighted the critical role national grocery chains play in fighting antibiotic-resistant “superbugs”.

In a nationwide poll, 86 percent of consumers said they thought meat raised without antibiotics should be available in their local supermarket. The majority of respondents (72 percent) were extremely or very concerned about the overuse of antibiotics in animal feed potentially creating “superbugs” that are resistant to antibiotics.

Americans are right to be concerned. Today, a whopping 80 percent of the antibiotics sold in the U.S.are used on farm animals that we eat, the vast majority of which are not even sick. This widespread abuse of antibiotics on factory farms—which involves routinely feeding antibiotics to farm animals to make them grow fatter faster and to compensate for crowded and unsanitary conditions—creates a dangerous breeding ground for “superbugs”, strains of drug-resistant bacteria such as E. coli, Salmonella, and Staph. These superbugs travel off the farm, putting consumers at risk of acquiring serious, and even life-threatening, infections.

The Natural Resources Defense Council (NRDC) is an international nonprofit environmental organization with more than 1.3 million members and online activists. Since 1970, they have worked to protect the world’s natural resources, public health, and the environment. Visit them at www.nrdc.org and follow them on Twitter @NRDC.